Micromechanical components, which are used, for example, in the automobile field as acceleration sensors, typically have a movable microstructure. The microstructure, which is also referred to as an MEMS structure (micro-electromechanical system), frequently includes a seismic mass (oscillating mass), which is suspended on a substrate via spring elements. In this case, an acceleration acting on the substrate results in a deflection of the seismic mass in relation to the substrate, which may be detected by suitable measuring methods. In order to delimit the deflection of the movable mass, a stop or a stop structure is conventionally used.
For example, delimiting the lateral movement of a seismic mass, i.e., parallel to a surface of a substrate, is described in German Patent Application No. DE 198 17 357 A1. For this purpose, the seismic mass has through openings, within which stop structures are situated. A micromechanical component is described in U.S. Pat. No. 7,121,141 B2, in which stops are implemented in the form of protruding structural elements on a bottom side of a seismic mass, in order to limit the movement of the seismic mass in the direction of a substrate.
Further micromechanical components having stop structures are described in European Patent Nos. EP 1 307 750 B1 and EP 1 947 053 A2, and U.S. Pat. No. 7,232,701 B2. For this purpose, the components have a functional substrate having a seismic mass and a cap substrate, which is connected to the functional substrate. The cap substrate has stop structures above the seismic mass, with the aid of which the movement of the seismic mass may be limited in a direction away from the functional substrate.
In conventional components, the problem exists that a stop structure may only be situated relatively imprecisely in relation to a seismic mass. This is the case in particular if seismic mass and stop structure are situated on different substrates (functional and cap substrates), which are connected to one another. The implementation of a small, precisely defined distance between stop and seismic mass is therefore only possible with a relatively great manufacturing complexity or not at all. Further disadvantages may be that limiting the deflection of a seismic mass is only possible “suddenly,” and a stop structure possibly has an undetermined electrical potential, whereby a reliable operation of a component may be impaired.